Powered by former Barcelona star Mariona Caldentey, Arsenal must upset the odds against the all-conquering Catalan giants on Saturday to prevent them from winning a fourth women's Champions League title in five years.
Reaching their sixth final in seven years, Barcelona aim to further tighten their grip on the women's game at the Jose Alvalade stadium in Lisbon against Renee Slegers' side.
The Dutch coach replaced Jonas Eidevall in October on an interim basis, made permanent in January as the team's form improved dramatically under her.
In the Champions League, Arsenal produced a stirring quarter-final second-leg comeback to eliminate Real Madrid and then thrashed record eight-time winners Lyon 4-1 in France to reach the final.
While Lyon are the record holders, Barcelona have been Europe's dominant force in the last five years.
The Catalans eased into their fifth consecutive final by destroying English domestic treble winners Chelsea 8-2 on aggregate.
SECOND QUADRUPLE ON THE CARDS
Barcelona, who won the Champions League in 2021, 2023 and 2024, also sealed a sixth-consecutive Liga F victory and are well-placed to repeat last season's quadruple.
They boast two-time Ballon d'Or winners Aitana Bonmati and Alexia Putellas as well as an array of other stars, although they have also lost some important players.
One of those is winger Mariona Caldentey, a regular for Barcelona over the last decade who went looking for a new adventure.
The 29-year-old joined Arsenal in July and has become the team's key player, named the Women's Super League player of the season.
"She has given us that next level," said Slegers. "She's a total footballer. She's got everything."
Barca winger Caroline Graham Hansen said it will be strange facing the Spaniard.
"Obviously, she's been missed because she's a very nice person inside the locker room and fantastic player on the pitch," said the Norwegian.
"So it's going to be weird to see her on the other side...
"(Hopefully) I won't see any goals from her on Saturday."
Of course, Caldentey has other plans.
"I hope I can score, but I wouldn't celebrate," she told Mundo Deportivo.
"I have a lot of respect for Barca for everything they gave me, how they helped me, and I'll always show that respect."
While Barcelona have three Champions League trophies in four years, Arsenal have won the competition just once, back when it was the UEFA Women's Cup in 2007.
This is their first Champions League final since then.
BACK TO THE START
The final is Barcelona's 100th European match, 13 years after their first, also against Arsenal.
Back then, the Gunners were a far greater force than their opponents and romped to a 7-0 aggregate win over Barcelona in the Champions League round of 32.
Kim Little scored in that tie and should feature for Arsenal in the final, along with the only other survivor from that era -- Barca's Putellas.
This season it took Barcelona some time to find their best under coach Pere Romeu, after Jonatan Giraldez left at the end of last season for US women's side Washington Spirit.
The Catalans also had to adapt to a new striker, Poland's Ewa Pajor, who has scored an impressive 43 goals in 45 matches this season.
"It's my dream to win this trophy with this team, but we have to be calm, not obsessive about this trophy," Pajor told UEFA.
"We have to be prepared, to be focused and I hope we win this trophy like a team, because we have amazing, amazing players, amazing coaches and, yes, we can do it."
Barcelona have won their last nine Champions League matches, scoring 44 goals in the process, one shy of Wolfsburg's record 45 in the 2013-14 season.
Claudia Pina has stepped up to fill the gap left by Caldentey and scored 10, making her the competition's top scorer, ahead of Arsenal's Alessia Russo and Caldentey on seven.